• Title/Summary/Keyword: loss function

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Change of Pulmonary Function after Pulmonary Resection (폐절제술후 폐기능 변화에 관한 연구)

  • 김용진
    • Journal of Chest Surgery
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    • v.18 no.3
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    • pp.517-528
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    • 1985
  • Pulmonary function studies today are generally accepted as an integral part of the evaluation of poor-risk patients who are to have pulmonary surgery. The effect of various pulmonary surgery on lung function was investigated in 54 patients in whom comprehensive lung function test were performed before and between 2 months and 14 months after operation at the Department of Thoracic Surgery, Seoul National University Hospital. According to the result of analysis, the effect of pulmonary resection on forced flow rate was keeping with the change of lung volume, and the preoperative level of ventilatory function plays a major role in determining postoperative loss of functioning lung. Although all measures of expiratory flow [FVC, FEV1, FEFO.2-1.2, MEF50, FEF25-75] have the same percentage of reproducibility, but FEV1 shows most sensitive, reliable linear correlation with the functioning pulmonary tissue loss than other parameters. The linear regression lines derived from the correlation between preoperative [X] and postoperative [Y] FEV1 on various surgical procedures were as follows: 1. Y = 0.57X 0.03. in pneumonectomy group of lung cancer[r=0.84]. 2. Y = 0.56X + 0.33. in lobectomy group of lung cancer[r=0.79]. 3. Y = 0.69X + 0.25. in lobectomy group of pulmonary infection[r=0.91].

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Development and Analysis of Fuzzy Overall Equipment Effectiveness (OEE) in TPM (TPM에서 퍼지 OEE 모형의 개발 및 분석)

  • Choi, Sungwoon
    • Journal of the Korea Management Engineers Society
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    • v.23 no.4
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    • pp.87-103
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    • 2018
  • This paper introduces the method to develop two main types of the fuzzy OEE (Overall Equipment Effectiveness) models via triangular membership function for measuring uncertainty. The fuzzy OEE includes model type 1 and model type 2. The model type 1 is used when the theoretical machine speed only reflects the time loss whereas model type 2 is used when the actual machine speed reflects both time and speed loss. Model type 2 has shown to perform a lower availability rate and a higher performance rate compared to model type 1. In addition, the fuzzy UPH (Unit Per Hour) which is derived from using the fuzzy OEE is presented to satisfy demand uncertainty. The fuzzy UPH can easily measure the fuzzy tact time and cycle time by reciprocating itself. Finally, this study demonstrates the fuzzy OEE models using IVIFS (Interval-Valued Intuitionistic Fuzzy Set) based on the characterization via membership function, non-membership function and hesitant function. For the purpose of analyzing the fuzzy system OEE, the OEE for each machine of plant structure is considered triangular interval-valued intuitionistic fuzzy number. Regardless of plant structure, the validity degree of fuzzy membership function of system OEE decreases when the number of machine with worst value of the validity degree increases. Corresponding examples are presented in this paper for practitioner to understand the applicability and practicability of the proposed fuzzy OEE methods.

ACL-GAN: Image-to-Image translation GAN with enhanced learning and hyper-parameter searching speed using new loss function (ACL-GAN: 새로운 loss 를 사용하여 하이퍼 파라메터 탐색속도와 학습속도를 향상시킨 영상변환 GAN)

  • Cho, JeongIk;Yoon, Kyoungro
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2019.11a
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    • pp.41-43
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    • 2019
  • Image-to-image 변환에서 인상적인 성능을 보이는 StarGAN 은 모델의 성능에 중요한 영향을 끼치는 adversarial weight, classification weight, reconstruction weight 라는 세가지 하이퍼파라미터의 결정을 전제로 하고 있다. 본 연구에서는 이 중 conditional GAN loss 인 adversarial loss 와 classification loss 를 대치할 수 있는 attribute loss를 제안함으로써, adversarial weight와 classification weight 를 최적화하는 데 걸리는 시간을 attribute weight 의 최적화에 걸리는 시간으로 대체하여 하이퍼파라미터 탐색에 걸리는 시간을 획기적으로 줄일 수 있게 하였다. 제안하는 attribute loss 는 각 특징당 GAN 을 만들 때 각 GAN 의 loss 의 합으로, 이 GAN 들은 hidden layer 를 공유하기 때문에 연산량의 증가를 거의 가져오지 않는다. 또한 reconstruction loss 를 단순화시켜 연산량을 줄인 simplified content loss 를 제안한다. StarGAN 의 reconstruction loss 는 generator 를 2 번 통과하지만 simplified content loss 는 1 번만 통과하기 때문에 연산량이 줄어든다. 또한 이미지 Framing 을 통해 배경의 왜곡을 방지하고, 양방향 성장을 통해 학습 속도를 향상시킨 아키텍쳐를 제안한다.

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The Effect of the Processing Conditions on the Magnetics Properties of Mn-Zn ferrite (제조공정에 따른 Mn-Zn 페라이트의 전자기적 특성변화)

  • 김종령;이해연;김현식;오영우;민복기
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.905-908
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    • 2001
  • The microstructure and the magnetic properties of Mn-Zn ferrite, which were power loss and saturation magnetic flux density, were investigated as the function of the process before firing. The highest initial permeability and the lowest power loss were attained to the specimen with CaO 400 ppm as a resulted from the highest solubility to SiO$_2$and the creation of liquid phase which improved sintering. The biggest grain size, the highest saturation magnetic flux density and the lowest power loss, which was resulted from that the eddy current loss increased as grain size increased but the hysteresis loss much more decreased and the hysteresis loss strongly influenced on the total power loss rather than the eddy current loss, were obtained to the Mn-Zn ferrite added 2wt% PVA. The power loss was lowest and the saturation magnetic flux density was highest in case of 1 ton/$\textrm{cm}^2$ and the grain size was not influenced.

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Bayesian Estimation of Uniformly Stochastically Ordered Distributions with Square Loss

  • Oh, Myong-Sik
    • Communications for Statistical Applications and Methods
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    • v.18 no.3
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    • pp.295-300
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    • 2011
  • The Bayesian nonparametric estimation of two uniformly stochastically ordered distributions is studied. We propose a restricted Dirichlet Process. Among many types of restriction we consider only uniformly stochastic ordering in this paper since the computation of integrals is relatively easy. An explicit expression of the posterior distribution is given. When square loss function is used the posterior distribution can be obtained by easy integration using some computer program such as Mathematica.

EMPIRICAL BAYES ESTIMATION OF THE TRUNCATION PARAMETER WITH ASYMMETRIC LOSS FUNCTION USING NA SAMPLES

  • Shi, Yimin;Shi, Xiaolin;Gao, Shesheng
    • Journal of applied mathematics & informatics
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    • v.14 no.1_2
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    • pp.305-317
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    • 2004
  • We construct the empirical Bayes (EB)estimation of the parameter in two-side truncated distribution families with asymmetric Linex loss using negatively associated (NA) samples. The asymptotical optimality and convergence rate of the EB estimation is obtained. We will show that the convergence rate can be arbitrarily close to $O(n^{-q}),\;q\;=\;{\lambda}s(\delta\;-\;2)/\delta(s\;+\;2)$.

Analysis of a Cylindrical Pin Fin with Variable Diameter (직경이 변하는 원통형 Pin 핀의 해석)

  • Kang, Hyung-Suk;Kim, Jong-Ug
    • Journal of Industrial Technology
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    • v.27 no.B
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    • pp.71-75
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    • 2007
  • A cylindrical pin fin with variable diameter is analyzed by using the one dimensional analytical method. Heat loss and fin efficiency are presented as a function of the fin diameter, length and convection characteristic numbers ratio. The relationship between the fin diameter and convection characteristic number over the fin for the same amount of heat loss is shown. One of the results indicates the fin efficiency increases as the fin diameter increases while that decreases as the fin length increases.

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A Loss-Minimization Nonlinear Torque Control for Electrical Vehicle Induction Motors (전기자동차용 유도전동기의 에너지 손실을 최소화하는 비선형 토크 제어기 설계)

  • Jang, Jin-Su;Han, Byung-Jo;Hwang, Young-Ho;Kim, Hong-Pil;Yang, Hai-Won
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.1838-1839
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    • 2006
  • In this paper, a loss-minimization nonlinear torque control for Electrical Vehicle(EV) induction motors is proposed. To improve the efficiency of the induction motors, it is important to find the optimal flux reference that minimize power losses. The proposed optimal flux reference is derived using a power loss function that is constructed with stator resistance losses, rotor resistance losses and core losses. And the time-varying load torque and the rotor resistance variation are considered in the power loss function. An algorithm that identifying the load torque is used. The rotor flux observer is used to obtain an accurate flux value regardless of the rotor resistance variation. Simulation results show a significant reduction in energy losses.

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Nutritional Management in Patients with Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환 환자의 영양관리)

  • Lee, Kwan-Ho
    • Journal of Yeungnam Medical Science
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    • v.21 no.2
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    • pp.133-142
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    • 2004
  • Chronic obstructive pulmonary disease(COPD) is characterized by a not entirely reversible limitation in the airflow. An airflow limitation is progressive and associated with an abnormal inflammatory response of the lung to gases and harmful particles. In COPD, the weight loss is commonly observed and there is a negative impact on the respiratory as well as skeletal muscle function. The pathophysiological mechanisms that result in weight loss in COPD are not fully understood. However, the mechanisms of weight loss in COPD may be the result of an increased energy expenditure unbalanced by an adequate dietary intake. The commonly occurring weight loss and muscle wasting in COPD patients adversely affect the respiratory and peripheral muscle function, the exercise capacity, the health status, and even the survival rates. Therefore, it is very valuable to include management strategies that the increase energy balance in order to increase the weight and fat free mass. A Better understanding of the molecular and cellular pathological mechanisms of COPD can improve the many new directions for both the basic and clinical investigations. The Nutritional supply is an important components of a multidisciplinary pulmonary rehabilitation program. Future studies combining an exercise program, the role of anabolic steroids, nutritional individualization, a more targeted nutritional therapy, and the development of new drugs including anti-cytokines is needed for the effective management of COPD.

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Optimum target values for manufacturing processes when drifting rate in the process mean is normally distributed (공정평균의 변화율이 정규분포인 제조공정의 최적 목표값)

  • Lee, Jae-Hoon;Park, Tae-Ho;Kwon, Hyuck-Moo;Hong, Sung-Hoon;Lee, Min-Koo
    • Journal of Korean Society for Quality Management
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    • v.38 no.4
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    • pp.540-548
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    • 2010
  • We consider the problem of selecting the most profitable initial process mean and length of production cycle for manufacturing processes subject to a constant linear trend during the same cycle that varies after resetting the processes. Assuming that the quality characteristic of interest is normally distributed, the optimum initial process mean and the length of production cycle are jointly obtained by minimizing the expected loss per unit time. We assume that the quality loss function due to the deviation from the target value is quadratic and resetting loss is constant. We consider both cases of symmetric and asymmetric quality loss function. An illustrative example is given and sensitivity analysis performed.